| The thesis includes three parts.Part I: ReviewA review of the application of the chromatography and interrelated sample pretreatment technologies in analysis of nutrient components and residues for pesticides and veterinary drugs in foods and the research status quo in home and abroad about almond-a famous nut food.Part II: Application of chromatography in analysis of almond'snutrient componentsThe amino acids in 13# almond kernel in Shanaxi Pucheng were analyzed by amino acid analyzer for the first time. The results indicated that there are 23.210% eighteen amino acids and 6.857% eight amino acids being indispensable to body in the almond kernel, and other active amino acids such as glutamic acid, arginine, aspartic acid, glycin, histidine are also rich in it.The optimal condition on extraction almond oil was established for the first time. Under the optical condition as follows: the power of ultrasonic wave 250W, frequency 40KHz, extraction by petroleum ether, material granularity 40mu, immersed time 36h, ultrasonic time 0.5h, solvent ratio 1:9 (W/V), the yield of 58.55% of almond oil was achieved. The fatty acids composition in Shannxi Pucheng almond oil was also analyzed by gas chromatography- mass spectrum (GC-MS) first. The results showed that the five kinds of fatty acids which include two saturated fatty acids (Octadecanoic acid and Hexadecanoic acid) that total content fall short of 9.0% and three unsaturated fatty acids (Oleic acid, 8,11-Octadecadienoic acid, and a smallquantity of 9-Hexadecenoic acid) that take up 91.48-91.87% of the all were discovered in the oil. The physical - chemical characterization of the oil was proved to be fine.The new method with high performance liquid chromatography (HPLC) for determining a- tocopherol in almond was set up. The results of determination of the almond in Shannxi Pucheng showed that there are 201.2~216.7mg/kg a- tocopherol in the kernel and 355.11 ~406.38 mg/kg a- tocopherol in the oil.The method with HPLC for determining vitamin C, vitamin Bl, vitamin B2 and vitamin B6 in almond was established. The results of determination of the almond in Shannxi Pucheng indicated that there are 4.27~4.53 mg/kg vitamin B2 and 0.799~ 0.838 mg/kg vitamin B1, and that vitamin C and vitamin B6 were not discovered in the kernel.The other components including moisture, ash, soluble sugar, crude protein, crude oil and mine elements in Shannxi Pucheng almond kernel were analyzed. The results showed that there are 4.22~4.70% moisture, 2.84~3.11% ash, 2.53~3.54% soluble deoxidized sugar, 4.98~5.16% soluble total sugar, 26.00~30.56% crude protein, 51.67~56.67% crude oil and nine abundant mine elements which content is K > P > Mg > Ca > Na > Fe > Zn > Mn > Cu, especially richer in Fe , Zn , K and Ca than some familiar nuts, and that the harmful elements -Pb, Cd,, Hg, As were not discovered in the kernel. So the almond belongs to a kind of excellent food.Part III. Application of chromatography in analysis of residues forpesticides and veterinary drugs in foodsThe method with solid-phase extraction(SPE) coupled with HPLC (SPE-HPLC) for the simultaneous determination of the twelve sulfonamides residues in egg powder has been established for the first time. The twelve sulfonamides and impurity in sample were completely separated in 22 min with isocratic elution. The 0.002-0.045mg/kg of limits of detection of the method for twelve sulfonamides were gained, which satisfy the requirements of detection the Maximum Residue Limits (MRL) of sulfonamides prescribed by CAC and Europe Union Organization (EUC)and some countries such as USA, Japan and Corea in foodstuffs. When added levels ranged between 0.1 g/g and 1.0 g/g standards, the average recoveries of 71.13 5.02%~99.53 5.13% to all sulfonamides in the sample were obtained, which accorded with the detection criterion of quality-control standardization in residues analysis. At present, this method is being declared country industry standard.The new method with solid-phase microextraction (SPME) coupled with gas chro...
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